Test Clojure master against all JDKs in Travis

Author: cichli

.travis.yml

@@ -11,6 +11,7 @@ env:
     - CLOJURE_VERSION=1.8 TARGET='test smoketest'
     - CLOJURE_VERSION=1.9 TARGET='test smoketest'
     - CLOJURE_VERSION=1.10 TARGET='test smoketest'
+    - CLOJURE_VERSION=master TARGET='test smoketest'
   global:
     - secure: "bCp4gU7XgeqLnqKwEpJarnKPbGljHyLE2rZnub4mEHD8kcvh6LoEkG/2QCtnSETj8zrQJwyMuEDGUwPgjmzQ/aEn6UiIYmv7ka6QnLBxOxhqQTbDtG7HssfkeT5b67LgOyQX7ejK88vnmH+OeWXM7kOOvUwVy5BVgsYyr2f1cGU="
     - secure: "D2Ie7dUZ9nQOIWtkRl2XWZeijSL8expUXP3GziSqQV1scJzwexxnUsRvWOkc2YU8+6IIGz9tcyt9RrEFUVF31VZgRSHh8P5rGGCzI2l99djKhYFfSErElwgoAJZFtOzougZK66/Gtb5uDo5L/wlKHkl4st3miqm+mEvfJITDjRQ="